Transcript Chapter 9 Balance Within Ecosystems

Chapter 9
Balance Within Ecosystems
Pages 311-339
An examples of captive breeding
is when zoos keep condors for
mating.
Lesson 4
If all members of a species
disappear from Earth, the
species is said to be extinct.
Lesson 3
The series of changes that occur
in an area where the ecosystem
has been disturbed but soil and
organisms still exist is secondary
succession.
Lesson 1
An example of how humans can
harm an ecosystem is
desertification.
Lesson 2
The number of different species
in an area is called biodiversity.
Lesson 3
Organisms that survive a
changing ecosystem have
adaptations that help them in
new conditions.
Lesson 1
The first species to populate an
area after primary succession
are pioneer species.
Pioneer species are carried to
areas by wind and water.
A species that does not naturally
occur in an area or brought in by
people is a nonnative species.
A species that is a major
influence on the survival of other
species in an ecosystem is a
keystone species.
Which two areas have the most
diverse ecosystems?
Rain forests and Coral reefs
Two human activities that lead to
extinction are hunting and
habitat destruction.
A diverse gene pool helps ensure
that individuals in species will pass a
variety of traits to their offspring.
Setting aside a marsh as a
wildlife refuge to protect
biodiversity is an example of
habitat preservation.
Illegal killing or removal of
wildlife from their habitats is
poaching.
The study of where organisms
live and how they got there is
biogeography.
The movement of organisms from
one place to another is dispersal.
An exotic species is an organism
that is carried into a new
location by people.
As the Earth’s plates move, the
continents move with them in a
process called continental drift.
What are two physical barriers
that limit distribution of species?
Water and Mountains
Why might species in a
population increase rapidly?
Limited predators
What kinds of scientists might be
involved in protecting
biodiversity? Biologists
The greatest genetic diversity
exists among species of
unicellular organisms.
Species that lack a diverse gene
pool are less able to adapt to
and survive changes in the
environment.
Species that could become
endangered in the near future
are called threatened species.
Decomposers break down dead
plants and animals and this adds
nutrients to the soil.
Habitat loss is a much more
important cause of extinction for
birds than mammals because
they rely on trees.
Poaching may be a more
important threat to mammals
than birds because birds are
harder to catch.
What are two endangered or
threatened species you have
heard about? giant pandas and
bald eagles
Brown pelicans are no longer
endangered because of a ban in
1972 on a pesticide called DDT.